Knock Sensor

Tiny
TBERNDTSON
  • MEMBER
  • 2004 FORD F-150
Check engine light on, computer show knock sensor code. If the 5.4 engine has 2 of them?
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Saturday, September 25th, 2010 AT 3:13 PM

29 Replies

Tiny
KASEKENNY1
  • EXPERT
That is correct. You have one for each bank. Your code should dictate which bank the code is for which will tell us which sensor the issue is with. I am attaching the info on these sensors for your review. Let us know what the actual code is and we can get more info if needed. Thanks

Here is a guide as well that will help with some general information:

https://www.2carpros.com/articles/how-a-knock-sensor-works
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Friday, November 27th, 2020 AT 6:25 PM
Tiny
FLICSTER
  • MEMBER
  • 2003 FORD F-150
  • 5.4L
  • V8
  • 2WD
  • AUTOMATIC
  • 185,000 MILES
Where is the knock sensor bank 1 located?
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Monday, December 7th, 2020 AT 4:39 PM (Merged)
Tiny
STEVE W.
  • EXPERT
The knock sensor is under the intake manifold. You remove the intake and unscrew the sensor. There is a pinpoint test you can do.

DG1- CHECK KS SENSOR RESISTANCE

Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.

Disconnect KS, measure resistance through the KS harness connector pins
Is resistance between 4.39 and 5.35 megaohms?
Yes = GO to DG2
No = For resistance less than 4.39 megohm: GO to DG3

DG2 - CHECK FOR OPEN OF KS CIRCUIT BETWEEN KS HARNESS CONNECTOR AND PCM HARNESS CONNECTOR
Disconnect PCM.
Measure resistance of the KS+ circuit between the PCM harness connector pin and the KS harness connector.
Measure resistance of KS- circuit between the PCM harness connector pin and the KS harness connector.
Is each resistance less than 5.0 ohms?
Yes = REPLACE KS.
No = REPAIR open circuit.

DG3 - CHECK KS CIRCUIT FOR SHORT TO GROUND IN HARNESS
Measure resistance between the KS- circuit at the PCM harness connector and chassis GND.
Measure resistance between the KS+ circuit at the PCM harness connector and chassis GND.
Is each resistance greater than 10,000 ohms?
Yes = GO to DG4
No = SERVICE short circuit.

DG4 - CHECK KS CIRCUITS FOR SHORT TO POWER IN HARNESS

Disconnect PCM.
Turn Key on.
Measure voltage between the KS+ circuit at the PCM harness connector and battery negative post.
Is the voltage less than 0.5 volt?
Yes = REPLACE PCM See: Programming and Relearning
No = SERVICE short circuit.

DG5 - CHECK KS CIRCUIT FOR INTERMITTENT FAULT
Key off.
Measure the resistance for KS+ between the PCM and KS harness connectors, while viewing the ohm meter, grasp the vehicle harness as close to the knock sensor(s) as possible. Shake and bend a small section of the harness from the KS sensor to the PCM.
Measure the resistance for KS- between the PCM and KS harness connectors, while viewing the ohm meter, grasp the vehicle harness as close to the knock sensor(s) as possible. Shake and bend a small section of the harness from the KS sensor to the PCM.
Tap the PCM and KS connectors if possible.
Are the resistance readings changing?
Yes = ISOLATE fault and SERVICE as required.
No = GO to DG6

DG6 - CHECK INTERNAL PCM RESISTANCE

Disconnect knock sensor (KS) harness connector.
Measure resistance between KS+ and KS- pins through the harness connector.
Is resistance greater than 10,000 ohms?
Yes = REPLACE KS. If concern is still present, REPLACE PCM See: Programming and Relearning).
No = REPLACE PCM See: Programming and Relearning.
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Monday, December 7th, 2020 AT 4:39 PM (Merged)
Tiny
MARK BINKLEY
  • MEMBER
  • 2001 FORD F-150
Engine Mechanical problem 6 cyl Two Wheel Drive Manual 237214 miles

I would like to know where the knock sensor is located on my 2001 F-150. Can you help me out with this puzzle? I love this site
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
KEN
  • ADMIN
The knock sensor for the v6 engine is at the rear of the engine block while the v8 engine has the sensor under the intake manifold. Here are some diagrams so you can see what I am talking about. (Below)

Please let us know if you need anything else to get the problem fixed.

Cheers, Ken
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
TOM GARDELLA
  • MEMBER
I have heard the knock sensor will be located on the right front of the engine for the 2001 F150 4.2L V6? Is this correct and could anyone post a diagram indicating its exact position? Thanks
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
DANNY L
  • MEMBER
Hello, I'm Danny.

Yes, you are correct. I've attached a picture below showing its location. Hope this helps and thanks for using 2CarPros.
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
BIGFOOT26
  • MEMBER
  • 2000 FORD F-150
  • 4.2L
  • V6
  • 2WD
  • MANUAL
  • 260,000 MILES
I have tried an tried to find and watch videos for this repair. And or pictures but cannot get a direct answer for the location for the sensor. All I have found was by the starter I have looked an cannot find this. Any information an pictures would greatly help.
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi and welcome to 2carpros. Com

It will be mounted to the cylinder head, either the front or rear. (If I recall it's the driver's side rear head) I attached a picture of its location to help you find it.

Let me know if this helps of if you have other questions.

Take care,
Joe
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
BIGFOOT26
  • MEMBER
Thank you very much
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi:
You are very welcome. Here are directions for replacement. The attached pic correlates with the directions.

_________________________

2000 Ford Truck F 150 2WD Pickup V6-4.2L VIN 2
Procedures
Vehicle Powertrain Management Sensors and Switches - Powertrain Management Sensors and Switches - Computers and Control Systems Knock Sensor Service and Repair Procedures
PROCEDURES
REMOVAL

pic 1

1. Remove the Knock Sensor (KS).
1 Disconnect the electrical connector.
2 Remove the bolt and the KS.

INSTALLATION
1. To install, reverse the removal procedure.

______________________

Take care and feel free to come back anytime.

Joe
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
MAVERICK10251984@AOL.COM
  • MEMBER
  • 1997 FORD F-150
V8 two wheel drive automatic 125,000 miles.

Where does the knock sensor plug into the front of the engine or the back? I cannot find the plug.
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
BLUELIGHTNIN6
  • EXPERT
The knock sensor will be located on the right front of the engine for the 4.2L and on the right side of the engine for the 4.6L and 5.4L engines. I can post diagram if you specify your correct engine size.
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
MAVERICK10251984@AOL.COM
  • MEMBER
The engine is a 4.6 V8.
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
BLUELIGHTNIN6
  • EXPERT


https://www.2carpros.com/forum/automotive_pictures/261618_Noname_1656.jpg

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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
JGANAWAY
  • MEMBER
  • 1993 FORD F-150
  • 4.9L
  • 6 CYL
  • 4WD
  • MANUAL
  • 270,000 MILES
Where is the knock sensor located on a 4.9?
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
KASEKENNY1
  • EXPERT
I attached the process from the manual to replace this sensor. Let me know if you need more info and we can dig something up. Check out the diagrams (Below). Please let us know what happens. Thanks
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Wednesday, December 9th, 2020 AT 8:54 AM (Merged)
Tiny
ROYF
  • MEMBER
  • 1986 FORD F-150
  • 5.0L
  • V8
  • 2WD
  • AUTOMATIC
  • 164,000 MILES
My truck is running erratically (no power, jerking, running very rich, etc.). I thought it may be the knock sensor, however when I checked the voltage to the knock sensor with the key on (engine not running) it was 1.9 volts. The Haynes manual states that it should be about 5 volts. Could this be a short or maybe a bad power control module?

Any help would be most appreciated!
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Wednesday, December 9th, 2020 AT 8:55 AM (Merged)
Tiny
HMAC300
  • EXPERT
Check fue lpressure first if fuel injected, autoparts rent gauge then check for a vacuum leak and yes if the voltage is not high enough it could be a bunch of things like a bad ecm an dor a shorted wire. But you should scan for codes first if you can
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-1
Wednesday, December 9th, 2020 AT 8:55 AM (Merged)
Tiny
ROYF
  • MEMBER
I thought about fuel pump, however the truck is running extremely rich. I scanned for the codes with an OBD and it showed the following: 22, 23, 25, 34, 72 and 73. I replaced the Throttle Position Sensor, the MAP sensor, the EGR Sensor and the O2 Sensor. I looked for a knock sensor, but could not find one. I retried the OBD and came up with: 22, 23, 31, 42, 72 and 73. The truck still performs very badly with a lot of backfiring into the intake if you try to accelerate too fast. I check the timing several times and it is right on the money. Any suggestions

RoyF
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Wednesday, December 9th, 2020 AT 8:55 AM (Merged)

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